The present invention relates to a spray pump, and in particular to a spray pump which sprays liquid contents and comprises an under cap 110; an over cap 120 engaged to the under cap 110; a cylinder housing 130 which is engaged to the bottom of the over cap 120 and has a suction through hole at its lower side and a check valve 132 installed at an inner, lower side of the top of the suction through hole; a stem 140 which passes through the over cap 120; a main spring 145 which is installed between the over cap 120 and an outer circumferential surface of the stem 140; a piston rod 150 which is engaged to the stem 140 and has at least two side passage holes 152 at a lower, side surface; a first seal cap 160 which is installed movable in upward and downward directions at the bottom of the piston rod 150; a second seal cap 170 which is engaged to the piston rod 150 at the top of the first seal cap 160; an inner spring 175 which is installed between the second seal cap 170 and the first seal cap 160; a first leakage discharge hole 135 which is formed at a side surface wall of the cylinder housing 130 and is positioned at the top of ‘the Highest Position of the first seal cap 160’ (shown as “H” in FIG. 2) and the bottom of ‘the Bottommost Position of the second seal cap 170’ (shown as “B” in FIG. 3); a second leakage discharge hole 136 which is formed at a side surface wall of the cylinder housing 130 and is positioned at the bottom of ‘the Highest Position of the second seal cap 170’ (shown as “H” in FIG. 2); a spray button 190 which is engaged to the top of the stem 140 and has a spray passage 191 communicating in a lateral direction; and a spray nozzle member 192 which is engaged to a discharge port of the spray passage.
A spray pump is sort of a pump which can spray liquid contents in mist forms when a user presses a button. The spray pump has been widely used so as to spray liquid cosmetic or liquid medicine which is generally stored in a container.
In terms of the spray pump, there are many examples such as the Korean Registration Patent No. 10-0485039 directed to “Spray pump for cosmetic container” (hereinafter referred to as “Patent Document 1”) or the Korean Published Patent No. 10-2000-0052881 directed to “The spray pump delivery system of the capacity which concentrated is reduced.” (hereinafter referred to as “Patent Document 2”).
As shown in FIG. 1, the spray pump for a cosmetic container of the patent document 1 has features in that in a housing 20 is provided a cylindrical guide tube 24 which protrudes upward for thereby partitioning a compression chamber 21 and an operation chamber 22, and from a lower, outer surface of a second valve 50 integrally protrudes a sealing ring 51 in an upward direction and with a certain elastic force, the sealing ring having a downwardly tapered surface. As the pressure in the compression chamber 21 increases, the sealing ring 51 widens in an outward direction for thereby enhancing air tightness with respect to a guide tube 24. In case of the prior art of the patent document 1, since a spring is provided in the housing 20, a metallic spring which serves to operate a pumping member comes into direct contact with the contents, which causes a corrosion of the metallic spring thanks to the contents.
Since only one leakage discharge hole is formed at the top of the piston ring 31, the leaked liquid gathered in a space except for a passage through which liquid can pass only when the piston ring 31 rises can be discharged, so it is impossible to obtain an efficient discharge of leaked liquid, and such operations seem inefficient. The above described problems also lie in the prior art of the patent document 2.